For using it you should have in the trac.ini file the [ticket-workflow] session because when a section for a ticket type doesn't exist trac uses the [ticket-workflow] for the actions to do.
If you want to define different workflows than you should create in trac.ini sections called [ticket-workflow-ticket_type] where ticket_type is the type of ticket you want to use this section,you can create all the sections you want and trac will use them when that kind of ticket is being used.